Tag Archives: Paleocene

3D model.

Fossil Friday: leg bones lead to extinct giant penguin in New Zealand

Science confirms: giant penguins exist(ed).

An amateur fossil find last year — large bird leg bones — confirm that giant penguins lived on New Zealand’s South Island millions of years ago.

Leg Bones.

Overview of the fossilized leg bones. Black scale bar is 50mm (~2in).
Image credits Gerald Mayr et al., (2019), AAJP.

Big Bird

The fossil “provides further evidence that penguins attained a very large size early in their evolutionary history,” according to the authors.

The bones belonged to a 80-kilogram bird that could grow to nearly 1.6 meters (63 inches) high, according to a new paper describing the fossils. Christened Crossvallia waiparensis, it hunted off New Zealand‘s coast in the Paleocene era, 66-56 million years ago.

It would make it roughly four times heavier and 40cm taller than the modern Emperor penguin, the researchers add.

3D model.

A life size 3D model of Crossvallia waiparensis.
Image credits Canterbury Museum.

New Zealand isn’t a stranger to extinct big birds. Between Haast’s eagle, with its three-meter wingspan and the flightless moa, which grew up to 3.6-meters tall, these beasts roamed both the land and the sky.

So there has been speculation that a species of large penguins also evolved here to take advantage of marine ecosystems — which the present findings prove correct.

“It further reinforces our theory that penguins attained great size early in their evolution,” says Canterbury Museum researcher Vanesa De Pietri, adding that this is the second giant penguin from the Paleocene era found in the area.

These ‘mega-penguins’ were likely driven extinct by the emergence of other large marine predators such as seals and toothed whales.

The paper “Leg bones of a new penguin species from the Waipara Greensand add to the diversity of very large-sized Sphenisciformes in the Paleocene of New Zealand” has been published in the journal Alcheringa: An Australasian Journal of Palaeontology.

Creationist finds Paleocene fossils in his basement, claims they’re 4,500 years old

An Alberta citizen discovered a trove of rare fossilized fish while digging up his basement. But Edgar Nernberg isn’t a man who “believes” in science – instead, he claims that the fish are 4,500 years old, from Noah’s flood, and the media seems OK with that. We’re not.

Darla Zelenitsky, palaeontologist and assistant professor at the University of Calgary, left and Edgar Nernberg, look over some of the fish fossils. Image via Calgary Herald.

Darla Zelenitsky, the University of Calgary paleontologist who was brought in to examine the five ancient fish dated the fossils at 60 million years, from a period called the Paleocene, the period that came after the Cretaceous. She was also delighted to find such well preserved fossils.

“I would give it a 10 out of 10 for significance,” said Zelenitsky. “There’s not very many complete fossils known in rocks of this age in Alberta,” she said about the fish, which are each about the size of a smartphone.

Because they lived relatively soon after the dinosaurs went extinct, they could answer some questions about evolution, and how life adapted after the catastrophic event at the end of Cretaceous.

Image via Global News.

“Plants and animals were actually recovering from the extinction at that time, so any fossils, particularly if they’re complete, are going to help us reconstruct what was going in the environment after a major mass extinction.”

But Nernberg, who is quite a well known person in the community, says he isn’t buying it.

“I subscribe to the creationist position, and I believe they were laid down in Noah’s flood, about 4,500 years ago. But we agree to disagree.”

The problem with this is that it’s not something you can agree or disagree on. You can discuss whether or not green is a nice color, or whether or not bears are cute – but whether or not some fossils are tens of millions of years old, or 4,500 years old is not really up for debate. Sure, they might not be 60 million years old, they may be 57, or 63, or 50 million years old, if Zelenitsky is really wrong, but four thousand years is simply not an option, and this is one of the main problems with how media portrays science: on the one hand, you have mister Edgar Nernberg, a known creationist without any education or expertise in the field of paleontology, and Darla Zelenitsky, who’s basically dedicated her life to studying fossils and has decades of learning and applying what she’s learned – and the media gives them equal coverage, and makes it seem like this is an actual uncertain debate. Spoiler alert: it isn’t. Some things simply aren’t up for debate, and this is one of them.

A computer forecast of how the ocean pH will look in 2100 under emission scenarios. Purple dots show cold-water coral reefs. Red dots show warm-water coral reefs. The pH scale is shown on the right. (Credit: NOAA)

Ocean life threatened by mass extinction as acidification rate nears 300 million year max

A computer forecast of how the ocean pH will look in 2100 under emission scenarios. Purple dots show cold-water coral reefs. Red dots show warm-water coral reefs. The pH scale is shown on the right. (Credit: NOAA)

A computer forecast of how the ocean pH will look in 2100 under emission scenarios. Purple dots show cold-water coral reefs. Red dots show warm-water coral reefs. The pH scale is shown on the right. (Credit: NOAA)

A newly published paper in the journal Science provides a worrisome report – the world’s oceans are acidifying at a rate, which if set to continue, will be unprecedented in the last 300 million years. The scientists report that this comes as a direct consequence of the alarming ever increasing carbon dioxide concentration in the atmosphere, which also gets absorbed by the oceans, with dramatic effects on the marine ecosystem.

To trace back the other periods of accelerated ocean acidification in Earth’s history, the scientists from the U.S. National Oceanic and Atmospheric Administration (NOAA) studied the isotopic composition of carbon changes found in marine rock samples. Rock records dating back as far as 300 million years were studied, which allowed tracking the ocean’s water pH over an impressive time frame. Thus, the researchers identified a number of key periods in Earth’s history when atmospheric CO2 concentration, and thus ocean water pH too, reached milestone levels. These spurred evolutionary changes, as well as  marine and animal extinction, like 65 million years ago when the dinosaurs died off.

An interesting period was the Paleocene-Eocene Thermal Maximum (or PETM), dating back 56 million years ago, when an abrupt carbon dioxide release caused a global temperature increase of 6°C over 20,000 years. During PETM, the oceans became 0.4 units more acidic on the 14-point pH scale. This period marked the largest deep-sea extinction of foraminifera of the last 75 million years, and was one of the four biggest coral reef disasters of the last 300 million years. The study authors warn that what happened 56 million years ago was a fast warm-up and quick acidification, however when compared with the current rate of CO2 levels increase and water acidification since the start of the industrial age 150 years ago, we’re currently on a trend that will far out shadow it.

Climate change comes in cycles, warming and cooling, and  the Earth has gone through a number of such periods during its history. It’s enough to compare some charts and time frames for relevancy to understand that there’s nothing really natural to what’s going on today on our planet, however. For instance, the first period the NOAA scientists decided to study was the end of the last ice, which started 18,000 years ago. Over a period of about 6,000 years, atmospheric CO2 levels increased by 30 percent, translating in a change of roughly 75 ppm – the same amount of increase was recorded in the past 50 years alone!

“Ocean acidification may have severe consequences for marine ecosystems,” reads the study. “However, assessing its future impact is difficult because laboratory experiments and field observations are limited by their reduced ecologic complexity and sample period.”

A similar report such as the from NOAA, was presented last summer at an U.N. conference. Then, the panel found that oceanic conditions are similar to those of “previous major extinctions of species in Earth’s history,” and that we face losing marine species and entire marine ecosystems, such as coral reefs, within a single generation.

Over the past 150 years, the Earth’s oceans have become more acidic by 0.1 unit of pH, and the study’s scientists predict that by 2100 there will be an increase to 0.2 or 0.3 pH.

“Given that the rate of change was an order of magnitude smaller compared to what we’re doing today, and still there were these big ecosystem changes, that gives us concern for what is going to happen in the future,” said Baerbel Hoenisch, one of the study’s lead authors.

source

A suggestive illustration portraying a modern day Morgan horse nose-to-nose to an artist's impression of the Sifrhippus sandrae, the first horse, which was just about the size of a house cat. (c) anielle Byerley, Florida Museum of Natural History

The first horse was the size of house cat and got even smaller as climate warmed 56 million years ago

Bergmann’s rule states that mammals of a given genus or species are smaller in hotter climates, and bigger in colder climates. Adapted, when faced with climate change cycles, mammals shirk as temperature rises and scale back up in size, once the cycle ends and makes room for cooling. Simple correlation, based on fossils and temperature readings from their given periods, seems to offer evidence supporting this principle – mammals shrink as the Earth warms. A latest study performed by scientists at Florida Museum of Natural History at the University of Florida, which looked at a brief, yet dramatic climate change,comes to the same conclusion.

A suggestive illustration portraying a modern day Morgan horse nose-to-nose to an artist's impression of the Sifrhippus sandrae, the first horse, which was just about the size of a house cat. (c) anielle Byerley, Florida Museum of Natural History

A suggestive illustration portraying a modern day Morgan horse nose-to-nose to an artist's impression of the Sifrhippus sandrae, the first horse, which was just about the size of a house cat. (c) Danielle Byerley, Florida Museum of Natural History

Called the Paleocene-Eocene Thermal Maximum or PETM for short, this period in Earth’s history took place 56 million years ago and was marked by significant global warming, which lead to a temperature increase between 9 to 18 degrees Fahrenheit at the start, only to drop to almost initial values at the end – the age lasted for 175,000 years. It may seem like a long time, but in geological terms, well it’s nothing more than a blink of an eye – still a lot had happen.

“We had known it was a really unique event for a while in the sense that it was a very rapid, large scale global warming event. And it marks one of the most important moments in mammalian evolution in the sense that we see the first occurrence of several modern orders of mammals, including the primates that are clearly traceable as the direct ancestors of the group that we’re a part of, as well as the ancestors of horses, the ancestors of cows and hippos and camels,” said Jonathan Bloch, associate curator of vertebrate paleontology at the Florida Museum of Natural History at the University of Florida.

The tiniest horse to roam the Earth

One such mammal was Sifrhippus, one of the first horse species, which  shrank from about 12 pounds average weight to about eight and a half pounds as the climate warmed over thousands of years. The first horses were a lot different from those of today; back then, they weren’t larger than a small dog or house cat. Interesting enough, the only Sifrhippus fossils found have been in Bighorn Basin of Wyomin, which today is the largest wild mustang reservation.

By studying various fossils like teeth or fragmentary jaws, the researchers were surprised to see the Sifrhippus become 30 percent smaller through the climate event , only to get 75 percent larger as it passed. They were able to tell this by studying the oxygen isotopes found in the horses’ teeth.

“What he showed was that exactly coincident with this body size change that we had documented there were shifts in the oxygen isotope that showed it was getting warmer as the horses were getting smaller. And then as the horses became larger again it became cooler,” Bloch said.

Indeed, the researcher’s findings conclude the change in size was, as suspected, driven primarily by the warming trend. A warmer climate seems to induce a shrinkage effect in mammals, which might be  able to shed excess heat easier.

Mammals and climate change today?

Right now, the Earth is warming at a constant rate, however the temperature increase ins’t taking place through thousands of years, but hundreds – induced by humans, if not accelerated. Will today’s mammals get smaller in the future as well? Well, late last year I wrote a piece on how climate change has lead to a lose in size of  3-17% for most plants, while fish shrank by 6-22% – polar bears, among others, have been reportedly getting smaller as well. So, this is already happening. As for humans, we’ve been getting bigger and bigger, mostly because of better nutrition – the same goes for the ego, only its food is gluttony.

The team of researchers’ findings were reported in the journal Science.

Story and illustration via NYT.